Submitted to: National Cotton Council Beltwide Cotton Conference
Publication Type: Proceedings
Publication Acceptance Date: January 8, 2000
Publication Date: N/A
Interpretive Summary: Electrostatic aerial spray systems offer potential for increased spray deposits and reduced spray drift from water-based spray mixes. A study was conducted to determine the feasibility of an aerial electrostatic system for applying a water-based spray mix of the insecticide malathion, as compared to the conventional ultra low volume (ULV) malathion sprays used in boll weevil eradication programs. Aerial spray results showed similar deposits of malathion for both systems, but the electrostatic water-based sprays were not as persistent as the oil-based ULV sprays of malathion. The electrostatic water-based sprays caused higher boll weevil mortality on the day of spray application. However, higher percentages of boll damage were sustained with the electrostatic application. These results show some initial efficacy benefit for the electrostatic system, but more rapid degradation of malathion from the water-based spray offset the initial benefit as shown by fruit damage results.
Technical Abstract: Boll weevil remains a significant cotton pest in many cotton production regions, and aerial applications of malathion are a significant control measure in boll weevil eradication programs. Aerial electrostatic spray systems offer possibility of increased spray deposits and reduced drift of water-based low volume sprays. A field study was conducted to compare spray deposits, weevil mortality, and fruit damage of electrostatically- applied EC malathion and ULV malathion treatments. Electrostatic applications gave higher weevil mortality on the day of application. However, persistence of the water-based electrostatic spray was lower than the oil-based ULV spray, which resulted in higher fruit damage for the electrostatic spray application.